[Trahald]

I hacked up a open gop patch. all it really does is change the idr interval higher and force i-frames in at the max-keyint and flag them as recovery points. then clears the reference list of all frames behind the i when the first non-b is ready to be encoded. So for the most part it just interferes with frame decisioning a little and does some reference maintenance. x264 already supported i (small i) frames so it was fairly easy.

in a very few tests i get about 1.5% smaller size. thats with both at b-adapt 1(x264 default). B-adapt 2 with open-gop gives 4% improvement over a closed gop encode at b-adapt 1 and 5% over b-adapt 2 with closed-gop. fades seem to do well bitrate wise also.

This patch really is only useful if you have small gops (ie bluray) . my tests were at min keyint of 12. This patch is not for your production encodes as it is experimental. Do not create any binaries with this patch that may be in automatic upgrading scripts to protect the innocent.

there will be 2 attachments. one is the patch by itself and one with hrd(interlaced) 13 patch on top of it (as hrd has to be adjusted to open gop and also the patches update the same part of encoder.c ). this hrd version does not replace the current hrd patch.

again both are experimental